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 */
package library.client;

import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import org.joda.time.DateTime;

/**
 *
 * @author emptak
 */
public class Tools {

    /**
     * taken from
     * http://www.anyexample.com/programming/java/java_simple_class_to_compute_sha_1_hash.xml
     * method computes sha1
     *
     * @param text to be hashed
     * @return hashed value
     * @throws NoSuchAlgorithmException
     * @throws UnsupportedEncodingException
     */
    public static String SHA1(String text) throws NoSuchAlgorithmException, UnsupportedEncodingException {
        MessageDigest md;
        md = MessageDigest.getInstance("SHA-1");
        byte[] sha1hash = new byte[40];
        md.update(text.getBytes("iso-8859-1"), 0, text.length());
        sha1hash = md.digest();
        return convertToHex(sha1hash);
    }

    private static String convertToHex(byte[] data) {
        StringBuilder buf = new StringBuilder();
        for (int i = 0; i < data.length; i++) {
            int halfbyte = (data[i] >>> 4) & 0x0F;
            int two_halfs = 0;
            do {
                if ((0 <= halfbyte) && (halfbyte <= 9)) {
                    buf.append((char) ('0' + halfbyte));
                } else {
                    buf.append((char) ('a' + (halfbyte - 10)));
                }
                halfbyte = data[i] & 0x0F;
            } while (two_halfs++ < 1);
        }

        return buf.toString();
    }
    
    private void a()
    {
        DateTime d = new DateTime();
        //d.g
    }
}
